I found it challenging and enjoyed your game.
Sadly some part of the challenge was me fighting with the movement system. Your game features a lot of precise platforming but your movement kit does not support precise platforming. Especially in the air the strength of the movement is just to strong.
I enjoyed the polarity aspects. For example that you cannot be killed by fire when in fire mode including projectiles. As well as being able to walk on ice enemies when you have the ice mantle.
Nice work!